Has anyone had any luck in replacing this part that connects to rear of engine. The pipe that connects to it is badly rusted leaving about an inch of is stuck in the outlet

 

Welcome to the forum

I assume a 2001 to 2011 2.3l Duratec engine Ranger

You pretty much have to pull out the transmission or pull out the engine to get access to that pipe
The 2.3l Duratec(Mazda L engine) was designed for FWD cars so transverse(sideways) mounting, putting the pipe/fitting in a easier to access place
So in the Rangers its a PITA same as PCV Valve access

Just plan on dropping transmission

 

As Ron mentioned, you'd need to drop the transmission to remove the aluminum water neck in the 2nd picture you posted. If you can just clean it out carefully with various tools, you can replace the steel crossover (pictured first) without removing the water neck from the back of the engine.

After doing so, you can use an engine cylinder hone and carefully clean up the cast tube if it has been damaged from corrosion. Or you can replace it, though no aftermarket company sells that piece, you'd have to purchase new OEM or used.

 

It wasnt easy but was able to remove it without dropping the transmission or engine. Considering the time it would of taken for either option they were my last resort...thx for the help